THE student who gunned down 32 people at Virginia Tech university in the deadliest shooting rampage in modern American history was a "troubled" loner, with a penchant for writing violent screenplays.

Once dubbed the "question mark kid" for failing to give his name in class, Cho Seung-Hui was a sullen, quiet individual, who preferred his own company to engaging with his fellow students.

The 23-year-old was believed to be taking medication for depression and was becoming increasingly violent, erratic and left a note in his dormitory in which he railed against "rich kids", "debauchery" and "deceitful charlatans" on campus, reports stated.

The letter, several pages long, is said to explain his actions and said: "You caused me to do this," according to US broadcaster ABC.

But police said there was no evidence of a suicide note and revealed they removed mostly documents following a search of his dorm room.

Classmates described an incident on the first day of a British literature class last year, in which the students were asked to introduce themselves. When it came to Cho's turn, he refused to speak.

Instead, on the sign-in sheet where everyone had written their names, Cho had written a question mark.

But it was his violence-laced scribblings that most alarmed his professors and classmates.

His creative writing was so disturbing that he was referred to the school's counselling service and described by one of his lecturers as "troubled", said Professor Carolyn Rude, chairman of the university's English department.

A student who attended Virginia Tech last autumn said Cho had written screenplays containing obscenities and violence for a playwriting class they had taken together.

One was about a fight between a stepson and his stepfather, and involved throwing of hammers and attacks with a chainsaw.

A second described students fantasising about stalking and killing a teacher who sexually molested them.

"When we read Cho's plays, it was like something out of a nightmare, former classmate Ian MacFarlane, wrote in an online blog.

He said he and other students "were talking to each other with serious worry about whether he could be a school shooter".

Cho arrived in the US from Seoul, South Korea in 1992 and was raised in suburban Washington DC, where his parents worked at a dry cleaners.

He graduated from Westfield High School in Chantilly, Virginia, in 2003.

Cho bought a a Glock 19 handgun and a box of ammunition, handing over #285 at a Virginia gun shop five weeks ago.

It was one of two guns found containing Cho's fingerprints. The serial number had been scratched off, but was traced using a receipt from his backpack.

Police said Cho's firearms were bought legally.

Grieving relatives, friends and survivors were told yesterday their loved ones "did nothing to deserve their fate" by George Bush as he addressed a memorial service.

US president George Bush, who attended a service at the university yesterday, said the victims shot dead were "simply in the wrong place at the wrong time" and left behind a "grieving nation".

Speculation is rife that Cho acted after a row with girlfriend Emily Hilscher, 18.

The animal science student is believed to have been the first to die at her dormitory in West Ambler Johnston Residence Hall.

Her neighbour, biology and English student Ryan Clark, 22, was also killed. He may have been trying to intervene, it was reported.

One posting by a friend on a page dedicated to Miss Hilscher on internet site Facebook said: "I'm sorry that she ever got involved with this guy."

Two hours later, Cho went on to attack staff and students at a separate university building, Norris Hall, half a mile away, leaving a further 30 victims.

Virginia Tech president Charles Steger said classes were cancelled for the rest of the week and Norris Hall would not be reopened this term.

He said counsellors were available around the clock to help students and staff come to terms with the tragedy.

A vigil was held at the university overnight for the second night running.

In South Korea, where Cho lived until 1992, President Roh Moo-hyun held a meeting with aides to discuss the shooting.

A statement has been released saying Roh was "shocked beyond description again over the fact that the tragic incident was caused by a South Korean native who has permanent residency in the US".

The president is expected to speak publicly about the massacre later today.

More details of the massacre emerged as the Blacksburg community struggled to come to terms with the full horror.

Police sources said chains and padlocks were used to lock doors at Norris Hall from the inside before the slaughter began.

There had been bomb threats on campus over the past two weeks but police have not determined whether they are linked to the shootings.

Witnesses reported that Cho, dressed in jeans and a black leather jacket, calmly and silently stalked students in classrooms and a stairwell.

People jumped from windows to escape the carnage as fellow students and staff carried away the wounded before emergency services arrived.

UK exchange student George Barnwell, 20, of Kings Heath, Birmingham, hid in his dormitory at Virginia Tech with his girlfriend when the gunman opened fire in the building next door.

In an internet posting, the Sheffield University engineering student, who is preparing to return home at the end of a year-long exchange, said he was in shock.

Heavily-armed police officers soon swarmed over the campus as one student used his mobile phone camera to record the sound of bullets.

Three lecturers were among the dead. Many victims were unofficially named on community websites and in student publications.

The police and university authorities have been criticised for not warning students of the danger.

The Virginia Tech massacre took place almost eight years to the day after the Columbine High bloodbath near Littleton, Colorado, on April 20 1999, when two teenagers killed 12 fellow students and a teacher before taking their own lives.

It is the second time in less than a year that the Virginia Tech campus has been closed because of gunfire.

Last August, the first day of classes was cancelled when an escaped jail inmate allegedly killed a hospital guard off-campus and fled to the area. A sheriff's deputy was killed just off campus.